Custom Audio Electronics VK80, Руководство пользователя

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The following igure shows an example of paper with the non-thermal paper printed with black marks and other graphics
(for example, a barcode): the outgoing voltage is constant while passing the white paper between two notches, presents
a peak at each black mark and presents some “noise” at each barcode.
In this case, the optimal value for the “Notch Threshold” parameter is located about halfway between the peak value and
the maximum value of the “noise” (as shown in igure).
THERMAL SIDE
NON-THERMAL SIDE
Peak
“Notch/B.Mark
Threshold”
Noise
If the maximum value of “noise” read by the sensor is very close to the peak value, it might be dificult to place the value
of the “Notch Threshold” at an intermediate point. In these cases, it is mandatory that the portion of paper between the
point of printing end and the front notch is completely white (no graphics). In this way, the only next graphic detected by
the sensor for alignment after the printing end will be the notch.
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